A new species of lava lizard (Iguanidae: Tropidurinae: Microlophus) from the Galápagos

Following Darwin's visit to the Galápagos in 1835, the species of lava lizards inhabiting the archipelago were scientifically described in the remaining decades of the 19th century. Notably, only a single species was found on each of the surveyed islands, with different species on most islands. Many species have also expanded their distributions onto surrounding islets. Based on morphological and genetic evidence, I describe herein a new species of lava lizard from the 0.8 km2 Gardner islet located 8 km east of the southern island of Floreana. The new species is most similar in morphology and coloration to its sister taxon M. grayii from Floreana and nearby Champion, Caldwell, and Enderby islets. Genetic distances, haplotype networks, reciprocal monophyly and differences in scale counts support recognition of specimens from Gardner as a new species. Finally, I discuss a potential biogeographic scenario leading to the evolution of the new species described in this paper.